The Oscar winners, known for their sardonic style, directed the spot for an environmental coalition as a media battle warms up over the role carbon fuels should play in America's energy future.

Academy Award winners Joel and Ethan Coen, known for their grimly comic portrayals of human nature, are poking fun at a new target: the coal industry.

The filmmaking brothers have directed a TV spot for an environmental coalition that's trying to demolish the notion that there's anything clean about so-called clean coal.

Launched Thursday, the ad follows a grinning, lacquer-haired pitchman whose can of "clean coal" air freshener sends a suburban family into coughing spasms when they spray a grimy cloud of it inside their spotless home.

The ad ends with a tag line: "In reality, there's no such thing as clean coal."

The spot is the latest salvo in the media battle between the coal industry and environmentalists over the role that carbon fuels should play in the United States' energy future.

The Obama administration has signaled its intention to move the nation toward clean, homegrown energy sources in an effort to boost energy security and fight global warming.

The nation's coal industry has gone on the offensive to persuade Americans that coal is part of the solution, not part of the problem. It has formed a trade group known as the American Coalition for Clean Coal Electricity, spending $18 million so far on television spots touting coal's abundance and the efforts being made to clean up this fuel, a major emitter of the greenhouse gases that are changing the Earth's climate.

"Meeting America's growing energy demand . . . is going to require the use of all energy technologies," said Joe Lucas, spokesman for the coalition. "Technology has made coal a cleaner energy option."

Lucas said the industry had spent more than $50 billion since the 1970s installing pollution-control equipment and designing plants that are more efficient. The industry is working on the next wave of innovation, he said, including carbon sequestration to capture carbon dioxide emissions and prevent their release.

The trouble, environmentalists say, is that the coal industry's marketing campaign has left Americans with the impression that such "clean coal" technology already exists. Such a breakthrough has yet to be developed and may never be at a cost that makes economic sense, said Bruce Nilles, national coal campaign director for the Sierra Club.

His nonprofit and four others -- the Alliance for Climate Protection, the League of Conservation Voters, the Natural Resources Defense Council and the National Wildlife Federation -- formed their own group last year to counter the coal industry's message. Known as the Reality Coalition, it has launched three TV spots since December mocking the notion of "clean coal."

Coalition spokesman Brian Hardwick said the sardonic script proposed by the group's advertising agency hooked the Coen brothers, who won 2007 Oscars for producing, directing and adapting "No Country for Old Men" and a 1996 Oscar for writing "Fargo."

"They thought it was their style," he said.

In a statement, the Coens said: "We were excited to be part of this important project and tell another side of the 'clean' coal story."

The spot is running on CNN, MSNBC, Comedy Central and can be viewed at www.this isreality.org.

The ad is humorous, but the stakes are serious.

Coal is the bedrock of U.S. electricity generation. About half of the nation's power is supplied by 600 coal-burning plants. The fuel is reliable, cheap and plentiful. The U.S. possesses about one-quarter of the planet's coal reserves.

But some scientists say that weaning the world off coal is crucial to slowing the devastating effects of climate change.